When receiving at a network edge node a number of data packets and transmitting these data packets through a network to a far end network edge node, the number of data packets lost during this transmission can be determined for the purpose of performance monitoring. Already known is a protocol for packet loss measurement as proposed in the publication “ITU-T Recommendation Y.1731—OAM functions and mechanisms for Ethernet based networks, (February 2008)”, briefly called Y.1731, which provides a method of packet loss measurement between two packet processors on which this protocol is implemented. Thus, two network edge nodes may determine the number of data packets lost during the transmission between their network ports, if at each of these network ports a packet processor running the protocol is provided. Therefore, a number of data packets lost between two clients, each connected to one of the network edge nodes, may be determined. It is an aim of the invention to improve the known method of packet loss measurement.